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Understanding the Reactivity Series

May 7, 2025

Reactivity Series KS3 Worksheet Notes

Overview

  • Objective: Understand the order of metal reactivity and apply this knowledge to various chemical reactions and applications.
  • Topics Covered: Reactivity series, chemical equations with metals, testing for gases, extraction methods, and displacement reactions.

Reactivity Order

  • Most Reactive to Least Reactive Metals:
    1. Potassium
    2. Sodium
    3. Calcium
    4. Magnesium
    5. Zinc
    6. Iron
    7. Lead
    8. Copper
    9. Gold

Key Chemical Reactions

  1. Reactions with Oxygen, Water, and Acids

    • Metal + Oxygen: Produces metal oxide.
    • Metal + Water: Produces metal hydroxide and hydrogen.
    • Metal + Acid: Produces salt and hydrogen.
  2. Specific Reactions

    • Magnesium burning in air: Forms magnesium oxide.
    • Copper in water: No reaction, as copper is not reactive enough.
    • Sodium with Hydrochloric Acid: Produces sodium chloride and hydrogen.

Testing and Extraction

  • Testing for Hydrogen Gas: Using a lit spill; a positive test results in a squeaky pop sound.
  • Extraction of Metals:
    • Metals more reactive than carbon are extracted via electrolysis.

Applications of Gold

  • Jewelry: Gold is used because it is very unreactive and does not react with skin.

Displacement Reactions

  • Rule: A more reactive metal will displace a less reactive metal from its compound.
  • Examples from Reactions:
    • Copper Sulfate + Magnesium: Magnesium displaces copper.
    • Magnesium Sulfate + Zinc: No reaction, as zinc is less reactive.

Reaction Equations

  • Word and Symbol Equations:
    • Copper Sulfate + Magnesium → Magnesium Sulfate + Copper
      • Symbol: CuSO₄ + Mg → MgSO₄ + Cu
    • Copper Sulfate + Zinc → Zinc Sulfate + Copper
      • Symbol: CuSO₄ + Zn → ZnSO₄ + Cu
    • Zinc Sulfate + Magnesium → Magnesium Sulfate + Zinc
      • Symbol: ZnSO₄ + Mg → MgSO₄ + Zn

Conclusion

  • Understanding the reactivity series allows prediction of reactions between metals and other substances.
  • Displacement reactions are a key application of reactivity knowledge.